Man has yet to invent a useful machine or a vehicle that can function throughout its designed useful life without some kind of maintenance or repair being performed. In fact, the lack of reasonable routine maintenance or repair will shorten the useful life of any asset, particularly for complex systems such as aircraft and manufacturing systems.
When a useful asset suffers a casualty in the field, there are a number isolation tests that may be applied to disambiguate the failure mode (“FM”), and then to narrow repair options down to a finite group of corrective actions (“CA”). Or conversely, to establish that a CA will not fix the FM. A CA may include either an isolation procedure or a repair procedure. Each isolation procedure and each related repair procedure has an estimated time cost and a material cost that are necessary to complete the procedure and also has a probability that the procedure will indentify and/or correct the FM.
With complex systems, such as aircraft, a casualty may result from a number of potential FM's that could be the underlying cause of the casualty. Each FM may have a particular probability of being the cause of the casualty. As a non-limiting example, an inoperative radio casualty may be caused by three probable FMs: a lack of electric power, a faulty circuit board, or a faulty squelch switch. Each FM may have an expected or a historical probability of causing that particular casualty. The probabilities of causing a particular casualty may be determined over time by testing or by historical performance and may be stored in a database for later use.
Further, it will be appreciated by those of ordinary skill in the art that some isolation procedures and repair procedures may be capable of identifying or correcting multiple FMs simultaneously, whether the FMs are related or not. Therefore, each repair procedure and isolation procedure has a probability of correcting or identifying one or more failure modes. Because one of a set of related FMs may have caused a casualty, the set of FMs is referred to as an ambiguity group. The more efficacy data that can be garnered from the field concerning the correction of an ambiguity group, the more accurate will be the correction probabilities and the lower the maintenance costs. As such, accurate feedback from maintainers is important to increase diagnostic accuracy and minimize maintenance cost. However, due to workload pressure and human nature often accurate maintainer feedback is not available.
Accordingly, it is desirable to capture as much relevant data concerning the correction of failure modes in complex systems that may be used to improve the maintenance of those systems. In addition, it is desirable to capture the relevant information despite any lack of repair feedback from the repair facility. Furthermore, other desirable features and characteristics of the present invention will become apparent from the subsequent detailed description of the invention and the appended claims, taken in conjunction with the accompanying drawings and this background of the invention.